1. Field of the Invention
This invention generally relates to couplings for plastic pipe, and more particularly to such couplings finding particular utility for repair or replacement of sections to previously installed pipes regardless of whether the pipes are in wet or dry condition.
2. Description of the Prior Art
Many different kinds of cementable pipe couplings are presently available, and are being satisfactorily used, for the installation of new plastic piping systems. However where repairs or replacements are to be made in existing systems, such available couplings are not satisfactory, or even usable without subsequent leakage, unless the pipe joint surfaces to be connected are completely "bone" dry since the presently available solvent type cements for plastic pipes will not properly seal if the surfaces are wet or moist.
Where repairs or changes are to be made in preexisting horizontal runs of plastic vinyl piping, for example, the system must first be completely drained, often over a long period of time of several hours, until the dripping of water entirely discontinues. If not, the mating surfaces of the pipes to be joined often become whetted, or moistened, reducing the effectiveness of the cemented joint seal.